Abstract: A new robot for hot-line sweeping of post insulators in substations is introduced.Working at high voltage,the robot has to be insulated.To ensure insulation,we use methods of insulated elevating scissors mechanism,insulated hydraulic system,two-level control system,optic fiber and wireless communication system,etc.The robot integrates technologies from high-voltage insulation,hydraulic driving,insulating material,wireless communication,vision,autocontrol,etc.